African American children living in the inner city are twice as likely to be hospitalized from asthma and five times as likely to die from asthma. Results from the National Cooperative Inner-City Asthma Study (NCICAS) indicate that 77% of inner-city homes have excessive cockroach allergen concentrations. Cockroach allergen reduction, therefore, has potential public health benefits if it can be shown to affect disease morbidity. The purpose of this study is to examine the effect of cockroach extermination and cleaning on asthma morbidity in children living in the inner city of Baltimore.